Government data underestimates the impact of social distancing in controlling COVID-19 spread Quantifying the mitigating impact of social distancing on the spread of COVID-19 is critical for evaluating the efficacy of social restrictions and informing future health policy decisions. While most studies have used government stay-at-home dates in their models, new research finds that individuals actually changed their behavior in reaction to the presence of COVID-19 in their state a median 12 days before a government lockdown. This underestimates the impact social distancing has in controlling the spread of the virus. The research, appearing in the American Journal of Preventive Medicine, published by Elsevier, examines sociodemographic variables as well and finds that individual behavior across certain groups may partially account for the disproportionate impact of COVID-19 on vulnerable communities in the United States.